Machine and method for winding reels of web material

ABSTRACT

The rewinding machine comprises: a first winding member ( 3 ) and a second winding member ( 9 ) defining a winding cradle ( 19 ); a winding rod inserter ( 25 ) for introducing a winding rod (A 1 ; A 2 ) in the winding cradle ( 19 ) to wind a reel (B 1 ) of web material (N) on said winding rod. The inserter ( 25 ) is arranged and designed for introducing the winding rod (A 2 ) against the first winding member ( 3 ) towards the winding cradle ( 19 ) and the second winding member ( 5 ) is designed and arranged to allow a previously formed reel (B 1 ) to be unloaded from the winding cradle ( 19 ).

TECHNICAL FIELD

The present invention relates to winding or rewinding machines forproducing rolls or reels of web material, such as paper, tissue paper,non-woven fabric and the like. The invention also relates toimprovements to the winding methods for producing rolls or reels of webmaterial.

STATE OF THE ART

In the paper converting industry and in other continuous web materialprocessing industries there is the need for producing reels or rolls ofwound web material constituting intermediate products for subsequentconverting operations. In the paper converting field, in particular, itis provided for a single or multiple ply of cellulosic material, forexample tissue paper, to be unwound and wound again on reels. Forproducing large diameter reels, designed to be subsequently unwound andrewound in small diameter logs that, cut orthogonally to their axis,producing single rolls for final consumption, start-stop rewindingmachines are used, i.e. machines wherein the feed of the web material isinterrupted or substantially slowed down when a reel has been completedto allow insertion of a new winding rod, around which the subsequentreel is formed, in the machine.

These rewinding machines usually have a winding cradle formed by twowinding rollers with substantially parallel axes. A winding rod ortubular winding core, around which the reel is formed, is inserted inthe nip formed between the two rollers. The reel is formed above the nipbetween the rollers with a gradual increase in diameter. In some cases athird movable winding-roller is also provided, which is gradually raisedas the reel diameter increases. Once winding has been finished, the feedis interrupted, the formed reel is unloaded from the winding cradle, theweb material is severed to form a tail of the finished reel and a headfor starting winding around a subsequent rod, the head is anchored to anew winding rod and this latter is driven into rotation in the windingcradle to start formation of the subsequent reel.

DE-A-3207461 schematically discloses a rewinding machine of this type.WO-A-2007/048872 describes a rewinding machine of the above mentionedtype, wherein the first winding member comprises a roller and the secondwinding member comprises a belt or a series of belts, driven around twoguide rollers. No means for unloading the reels are described.

U.S. Pat. No. 4,456,190, IT-B-1130631, U.S. Pat. No. 4,635,867, U.S.Pat. No. 4,552,316 and DE-A-3151256 disclose rewinding machines of theabove mentioned type, wherein the reel is unloaded by a side pusher thatpushes the reel laterally to make it roll outside the winding cradle. Aseparate insertion means inserts a new rod or tubular winding core. Inthese machines the subsequent winding rod or core is introduced in thewinding cradle from the top, i.e. it is put on the winding rollers.

U.S. Pat. No. 5,577,684, GB-A-2065081, U.S. Pat. No. 4,974,786, U.S.Pat. No. 4,516,735, U.S. Pat. No. 3,918,654 and U.S. Pat. No. 5,911,384describe rewinding machines of the above mentioned type, wherein asingle pivoting member, arranged on a side of the winding cradle, notonly unloads the formed reel to move it away from the winding cradle,but also inserts a new winding rod or core in said cradle from the top.

U.S. Pat. No. 3,841,578 discloses a rewinding machine with a pair ofwinding rollers defining a winding cradle. The machine further comprisesa side roller, which pushes the reel, once it has been completed, tomove it away from the winding cradle. Once the reel has been at leastpartially ejected from the winding cradle, the winding rollers are movedaway from each other. The reciprocal movement away of the two windingrollers allows the insertion from the bottom of a new winding rod. Thiswinding rod passes across the nip defined between the two rollers, whichat are then moved towards each other again to support the new windingrod or core and to start winding of a new reel around the new coreinserted from the bottom upward.

U.S. Pat. No. 4,842,209 and US-A-2004/0159737 disclose rewindingmachines of the above mentioned type, wherein the new winding core isinserted from the bottom after having moved the winding rollers,defining the winding cradle, away from each other. In these machines oneof the two winding rollers also provides for a series of belts drivenaround the same roller and around a third guide roller. The reel iswound by maintaining it always in contact with the first and the secondwinding roller. Once winding has been finished, the reel is moved awayfrom the winding cradle and brought in contact with the belts entrainedaround the second winding roller. The belts act as a transfer elementfor transferring the reel from the winding cradle towards an unloadingarea. When the formed reel is on the belts, the winding rollers can bemoved away from each other in order to insert, through the nip definedbetween them, the new winding core, which is lifted from the bottomupward. Once the end position of the winding rod or core has beenachieved, the winding rollers are moved towards each other again toallow starting winding of the new reel.

One of the critical aspects of these machines is the continuity of thewinding process. The high dimension of the formed reels and theoperation complexity of unloading the reels and inserting new windingrods often require for the web material feed to be completely stoppedonce a reel has been completely wound, in order to allow: the insertionof a new winding rod or core, the severing of the web material, theanchoring of the head thereof on a new winding rod or core, the start ofthe winding of the new reel.

These start and stop cycles entail production losses as well as stressesin the production line.

In winders for producing very large diameter reels, for example windersarranged downstream of the continuous paper machines, winding means areprovided with a single winding roller and a pair of guides. The reel isformed around a winding rod, which is pressed against the winding rollerand is supported on the horizontal rectilinear guides extending from thewinding roller towards a reel unloading area. Usually a winding rodinserter is provided in these winders, which brings the winding rodagainst a single winding roller to wind a reel. The whole winding cycleis performed through this single winding roller, against which the reelis pushed by a pair of slides engaging the ends of the winding rod andgradually moving away from the winding roller as the reel diameterincreases. Examples of this kind of machines are described inWO-A-2009/049867; EP-A-0943569; DE-A-19944295; EP-A-1571109;EP-A-1245515; U.S. Pat. No. 6,145,778; EP-A-1071627; GB-A-2188619; U.S.Pat. No. 6,047,916.

U.S. Pat. No. 2,989,262 discloses a machine comprising a first windingroller and a second winding roller, which define a winding cradle. Themachine also comprises a winding rod inserter for introducing a windingrod in the winding cradle at the start of each cycle. A reel of webmaterial is wound around the winding rod. The inserter is arranged anddesigned so as to introduce the winding rods against the first windingroller towards the winding cradle. Once a reel has been completelywound, the web material is severed, the machine is stopped, the reel isunloaded from the winding cradle and subsequently the new winding rod isinserted to start a new winding cycle of a new reel.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a new rewindingmachine and a new winding method that overcome, wholly or partially, oneor more drawbacks of the known machines.

According to one aspect, the invention relates to a rewinding machinecomprising: a first winding member and a second winding member defininga winding cradle; a winding rod inserter for introducing a winding rodin the winding cradle and for winding a reel of web material on saidwinding rod, as well as a system of roller(s) suitable to control thereel diameter increase. The inserter is advantageously arranged anddesigned so as to introduce the winding rod against the first windingmember towards the winding cradle; and the second winding member isdesigned and arranged to allow a previously formed reel to be stoppedand unloaded from said winding cradle. In this way, while a formed reelis unloaded from the winding cradle, a new winding rod is insertedtowards the winding cradle and starts to wind around itself a secondreel of web material as a result of the contact with only one of the twowinding members. The two winding members can be thus controlledindependently of each other, the first one to start winding a new reeland the second one to stop and unload a reel that has been completedduring the previous winding cycle. The cycle of unloading the reel andstarting winding a new reel is therefore faster and can be performedwithout stopping the machine. The feed speed of the web material ispreferably reduced during the reel unloading, but it is not stopped. Thespeed reduction is substantially lower than the reduction necessary inother known rewinding machines, with consequent advantages from aproductivity viewpoint too.

In particular, the object of the present invention is a rewindingmachine comprising:

-   -   at least a first winding member and a second winding member        defining a winding cradle;    -   a winding rod inserter for introducing a winding rod in the        winding cradle to wind a reel of web material on said winding        rod, said inserter being arranged and designed so as to        introduce said winding rod against the first winding member        towards said winding cradle;        characterized in that: the second winding member has a variable        configuration and, if necessary, a variable speed according to a        law different from that of the speed of the first winding        member, and is designed and arranged to allow a reel, formed        around a first winding rod, to be unloaded from said winding        cradle, through a change in the configuration of said second        winding member; and that said inserter, said first winding        member and said second winding member are controlled such that        said reel of web material wound around said first winding rod is        unloaded from said winding cradle through a change in the        configuration and, if necessary, in the speed of the second        winding member, whilst said inserter moves a second winding rod,        that can be previously brought to the line speed, towards the        first winding member and said first winding member brings said        second winding rod into rotation.

In advantageous embodiments the first winding member comprises a firstwinding roller. According to preferred embodiments of the presentinvention, the second winding member can comprise a flexible element,for example a belt or a series of belts, entrained around a secondwinding roller and a guide element, for instance a roller or a series ofpulleys.

In some embodiments the first and the second winding roller are arrangedwith parallel, preferably horizontal axes. In preferred embodiments, thedistance between the centers of the rollers is fixed, i.e. not variableduring the normal operating cycle. The winding rods are preferably movedtowards the winding cradle, defined by the two winding rollers, from thesame side on which the reel is formed, i.e. without passing through thenip between the two winding rollers. The web material is preferably fedaround one of the winding rollers, again without passing through the nipbetween the two winding rollers.

In some preferred embodiments of the present invention the first windingroller and the second winding roller are motorized through distinctmotors advantageously controlled by a control unit to change therotation speeds of the two winding rollers differently one from theother during the winding cycle.

To unload the formed reel from the winding cradle, the second windingmember has preferably a variable arrangement in shape and/or positionand/or speed. In some preferred embodiments of the invention, when thesecond winding member comprises a winding roller and a flexible elementor member entrained around the winding roller and around another guidemember, the arrangement can be such that the flexible member or elementtilts to unload the reel. For example it can be lowered to transfer theformed reel from the winding cradle towards an unloading station.Tilting can be performed around the axis of rotation of the secondwinding roller.

In some embodiments, with the first winding roller guiding surfaces canbe associated, against which the inserter rests said winding rods.

In some embodiments the guides are advantageously arranged and designedto define a winding rod-introduction trajectory, extending around thefirst winding member and moving gradually towards said winding memberfrom a non-contact position to a contact position of the winding rodwith the web material driven around said winding member. The guides canbe driven to put the new rod into rotation, so as to have asubstantially synchronous speed with the web material before the contactthereto. In other embodiments the inserter can comprise one or two jawsor other engaging members for engaging the winding rods, controlled soas to impart to the winding rod a trajectory of gradual movement towardsthe first winding member and to control the rod in the first windingphase of the web material. The jaws or other engaging members and/or thewinding rods can be designed so as to allow the winding rod to rotatearound its own axis when the rod is still engaged with the inserter butinto contact with the first winding member, which imparts a windingrotational movement to the winding rod.

In preferred embodiments of the invention, the first winding member, thesecond winding member and the inserter are controlled such that, while acompleted reel is unloaded from the winding cradle by a movement of thesecond winding member, said inserter brings a winding rod to co-act withthe first winding member to engage and start winding the web materialaround said winding rod. The inserter is advantageously controlled tomaintain said winding rod resting on said first winding member for afirst winding phase of the web material around said winding rod, beforesaid winding rod starts to rest on the second winding member.

The invention also relates to a rewinding machine comprising at least afirst winding member comprising, or formed by, a first winding rollerand a second winding roller defining a winding cradle; and, in addition,a winding rod inserter for introducing a winding rod towards the windingcradle to wind a reel of web material around the winding rod. Theinserter is arranged and designed so as to introduce the winding rodagainst the first winding roller towards the winding cradle; and thesecond winding member comprises a second winding roller, a guide elementand a flexible element entrained around the second winding roller andaround the guide element. The second winding member designed in this waycan change in configuration, i.e. in the reciprocal position of theparts composing it, to unload a previously formed reel from the windingcradle. The first and the second winding roller advantageously form thewinding cradle wherein the main part of the winding cycle occurs.

In some embodiments the rewinding machine comprises a first windingmember, comprising a first winding roller, and a second winding member,comprising a plurality of further winding rollers, preferably withvariable center-to-center distances. In some embodiments the windingrollers forming the second winding member define a cluster of windingrollers. The cluster of winding rollers forming the second windingmember can be advantageously controlled and arranged so as to be incontact with a reel of web material. In some embodiments, at least someof said winding rollers forming said second winding member are movableso as to move a completed reel away from the first winding member andtowards an unloading area, for instance towards an unloading station,which can comprise a pivoting cradle receiving the reel and transferringit towards a pick-up area. According to some embodiments, the windingrollers forming the second winding member are advantageously controlledso as to maintain in rotation the reel being completed and to continuewinding the web material around the reel, while said reel is transferredtowards the unloading area and the inserter moves a new winding rodtowards the first winding member. The first winding member and thesecond winding member advantageously comprise independent motors torotate a first winding roller, being part of or constituting the firstwinding member, and a second roller, being part of the second windingmember, at speeds independent of each another.

The speed of the winding members can change from a steady-state speed,or winding speed, to an exchange speed or replacement speed, at whichthe reel being completed moves away from the first winding membertowards an exchange area. The second winding member can be controlled soas further to slow down from the exchange or replacement speed to areduced speed, at which the reel being completed is brought. Thisreduced speed is lower than the exchange speed. When the reel rotates ata reduced peripheral speed, lower than the exchange speed, at which theweb material is temporally fed, a loop can be formed, which facilitatesthe step of severing the web material and starting winding a new reel ona new winding rod.

In some embodiments the second winding member comprises a cluster or setof winding rollers comprising a second winding roller, a third windingroller and a fourth winding roller. In advantageous embodiments thefirst winding roller and the second winding roller are arranged with apreferably fixed center-to-centre distance, and form therebetween a nipor seat for resting and rotating the reel being wound. In someembodiments an auxiliary winding roller is arranged between the firstwinding roller of the first winding member and the second windingroller, forming part of the second winding member. The auxiliary windingroller can have a fixed axis or a movable axis to follow the diameterincrease of the reel being formed.

In some embodiments, when the second winding member comprises a clusterof winding rollers comprising a second, a third, and a fourth windingroller, said third winding roller and said fourth winding roller arearranged and controlled such as to move the first reel away from thefirst winding member and to transfer it towards said unloading area. Thetransfer can occur by maintaining the reel in contact with the secondwinding roller. In other embodiments the third winding roller iscontrolled such as to move away from the reel whilst the fourth windingroller is displaced to transfer the reel from the winding area towardsthe unloading area. In some embodiments at least some of the rollersforming the second winding member are controlled such as to slow downand then to stop the reel rotation.

If the second winding member comprises a cluster of winding rollers, insome embodiments one of said winding rollers of the cluster remains in afixed position, whilst at least one other of said winding rollers of thecluster is used to displace the reel, making it roll on the windingroller, which remains in fixed position. The rotation speed of at leastsome of the rollers of the cluster of rollers forming the second windingmember is controlled to slow down and then to stop the reel rotation.Slowing down can occur in two steps: in a first step, slowing down ofthe reel rotation corresponds to a reduction in the feed speed of theweb material and therefore to it corresponds also a slowing down of thefirst winding member. In a second step the first winding membercontinues to move at the feed speed of the web material, whilst therollers of the second winding member further slow down and then stop therotation of the formed reel.

In some embodiments the second winding member comprises a cluster ofwinding rollers comprising a second winding roller, a third windingroller, and a fourth winding roller, which are controlled to slow downand then to stop the rotation of said first reel, whilst the inserterbrings a second winding rod against the first winding roller, startingwinding a second reel around said second winding rod in contact withsaid first winding roller, whose rotation is not stopped during thereplacement phase.

Preferably, the winding rod inserter is associated with angularacceleration means for the winding rods to drive each winding rod intorotation before it is brought in contact with the web material. Eachwinding rod is advantageously accelerated by said angular accelerationmeans, so as to have a peripheral speed substantially equal to the feedspeed of the web material when the winding rod comes in contact with theweb material.

In advantageous embodiments, winding starts by holding the web materialbetween the new winding rod and the first winding member, whilst theperipheral speed of the first winding member and of the winding rod aresubstantially equal and nearly corresponding to the feed speed of theweb material.

According to a different aspect, the invention relates to a method forproducing reels of web material around winding rods, comprising thesteps of:

-   -   winding a first reel of web material around a first winding rod        in a winding cradle comprising a first winding member and a        second winding member,    -   once said first reel of web material has been wound, unloading        said first reel of web material from said winding cradle,        inserting a second winding rod in said winding cradle, and        winding a second reel of web material around said second winding        rod;        wherein the first reel of web material is unloaded from the        winding cradle through a change in the arrangement of the second        winding member, while the second winding rod is driven into        rotation by moving it towards the first winding member.

According to some embodiments of the invention the first reel of webmaterial is unloaded from said winding cradle by making the secondwinding member pivot from a winding position to an unloading position.

In one embodiment, the method according to the present inventioncomprises the steps of:

-   -   slowing down the winding speed;    -   modifying the arrangement of the second winding member from a        winding position towards an unloading position thus moving the        first reel away from the first winding member and towards an        unloading area;    -   bringing the second winding rod against the first winding        member, causing the second rod to start rotation, and starting        to wind the web material around the second rod to form the        second reel;    -   bringing the second winding member towards said winding position        again and bringing the second reel under formation around the        second winding rod in contact with said second winding member.

According to a further aspect of the present invention a rewindingmachine is provided, comprising: a first winding member and a secondwinding member defining a winding cradle; and a winding rod inserter forintroducing a winding rod in said winding cradle to wind a reel of webmaterial on said winding rod. Advantageously, the second winding memberhas a variable configuration to unload a formed reel from said windingcradle; and the inserter is arranged and controlled to transfer saidwinding rod along a movement path towards said first winding member,along said path the web material being engaged to said winding rod tostart winding around said winding rod driven into rotation by said firstwinding member.

The invention also concerns a winding method comprising the steps of:

-   -   arranging a first winding roller and a second winding roller to        define a seat or cradle for supporting and rotating the reel        being wound;    -   arranging a third winding roller and a fourth winding roller        with movable axes;    -   winding a first reel in said support and rotation seat in        contact with at least said first winding roller and said second        winding roller;    -   continuing winding said first reel of web material between said        first winding roller, said second winding roller, said third        winding roller, and said fourth winding roller;    -   moving said first reel of web material away from said first        winding roller maintaining it into rotation through at least        said second winding roller and said fourth winding roller and        reducing the rotation speed of the reel from a winding speed to        a replacement speed, lower than the winding speed;    -   bringing said second winding rod against said first winding        roller and engaging the web material between said first winding        roller and said second winding rod,    -   severing the web material between the second winding rod and the        first reel;    -   starting winding a second reel around said second winding rod;    -   moving the first reel of web material away from the second        winding roller;    -   bringing the second reel in contact with said second winding        roller.

According to some embodiments of the method according to the invention,it is provided for said first reel of web material to be moved away fromsaid first winding roller while maintaining it into rotation by means ofsaid second winding roller, said third winding roller, and said fourthwinding roller.

Whilst the first reel is moved away from the first winding roller, thethird winding roller is preferably moved away from the first reel andthe first reel is transferred towards the unloading area by means of thefourth winding roller.

In some embodiments of the method according to the invention it isprovided that the rotation speed of the first reel is reduced by slowingdown the second winding roller, the third winding roller and the fourthwinding roller; that the third winding roller and the fourth windingroller are moved away from the first reel; said third winding roller andsaid fourth winding roller are accelerated until the winding speed andsaid second winding rod and the reel being formed around it are engagedwith said third winding roller and said fourth winding roller.

In some embodiments the winding method provides the steps of: forming aloop of web material between said first reel and said second winding rodslowing down the rotation speed of said first reel; and of holding saidloop of web material between said second winding rod and said firstwinding member and causing the severing of the web material between saidfirst reel and said second winding rod.

According to a further aspect of the present invention, a rewindingmachine is provided, comprising: a first winding member and a secondwinding roller defining a winding cradle; a winding rod inserter forintroducing a winding rod in said winding cradle to wind a reel of webmaterial on said winding rod, said inserter being arranged and designedso as to introduce said winding rod against the first winding rollertowards said winding cradle; a plurality of further winding rollers withmovable axes arranged and controlled to unload a reel from said windingcradle whilst said inserter brings a new winding rod against said firstroller to start winding a new reel of web material. The winding rollerscan be advantageously controlled to slow down the reel and subsequentlyto stop it. Advantageously, the winding rollers hold the reel betweenthe second winding roller and said further winding rollers during thephase of moving away from the cradle, slowdown and stopping; preferablythe second winding roller remains fixed, i.e. it doesn't rotate, untilwinding starts around the new rod maintaining the new rod in contactonly with the first winding member, for instance by using the inserter.

In some embodiments of the invention a rewinding machine for producingreels of web material wound around winding rods is provided, comprisinga first winding roller, a second winding roller defining with said firstwinding roller a winding cradle; an inserter for introducing windingrods in said winding cradle; a cluster of further winding rollers withmovable axes, co-acting with said first winding roller and said secondwinding roller to maintain in rotation a first reel being formed and tomove said first reel away from said winding cradle, to slow down saidfirst reel and lastly to stop said first reel, whilst said inserterintroduces a new winding rod towards the first winding roller, saidfirst winding roller starting winding a new reel around said new windingrod. The machine can advantageously provide for severing means forsevering the web material. In some embodiments the severing meanscomprise air blows. The winding rollers can be controlled to generate aloop of web material, which is engaged around the new winding rod. Theloop of web material can be formed by changing the rotation speeds ofthe winding rollers, and in particular by slowing down the secondwinding roller with respect to the first winding roller.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by following the descriptionbelow and the attached drawing, which shows a non-limiting practicalembodiment of the invention. More in particular:

FIGS. 1 to 5 show a schematic side view of a rewinding machine accordingto the invention in an operating sequence comprising the formation of acomplete reel, its unloading, and the introduction of a new winding rodto start formation of a second reel;

FIGS. 6 to 14 schematically show a machine according to the invention ina different embodiment and a sequence of the operations performed duringa winding cycle;

FIGS. 15 to 23 show the machine of FIGS. 6 to 14 in a differentembodiment of the winding and replacing cycle of a formed reel with anew winding rod;

FIGS. 24 to 32 show a further variant of the operation of the machine ofFIGS. 6 to 14; and

FIGS. 33 to 40 show a third embodiment of a machine according to theinvention and a related winding and replacing cycle of a formed reelwith a new winding rod.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The rewinding machine, indicated in its entirety with number 1,comprises a first winding member 3 and a second winding member 5. Insome embodiments the first winding member 3 is constituted by, orcomprised of, a winding roller rotating around a substantiallyhorizontal axis 3A. The rotation of the roller is controlled by anelectric motor, schematically indicated with number 7.

In some embodiments, the second winding member 5 comprises a secondwinding roller 9 rotating around a substantially horizontal axis 9Asubstantially parallel to the axis 3A of the winding roller 3. Thewinding rollers 3 and 9 form a nip therebetween and define a windingcradle.

In some embodiments the winding roller 9 is driven into rotation by asecond motor 8, distinct from the motor 7. The motors 7 and 8 arepreferably connected to a central control unit 10, with which also theother members of the machine are interfaced to perform the winding cycledescribed below. The control unit 10 can be a programmablemicroprocessor unit, preferably connected to a panel, a display, a touchscreen, a keyboard, or other user interface means.

In some embodiments one or more belts 11 are advantageously provided,entrained around the winding roller 9 and around a roller 13, connectedto the roller 9, for instance through a pair of arms 15. In somepreferred embodiments of the invention the arms 15 are supportedcoaxially to the roller 9 and therefore pivot around the axis ofrotation 9A of the winding roller 9. Pivoting can be controlled by ahydraulic or pneumatic cylinder-piston actuator, or by a rotatingactuator, for example by an electric motor. The actuator controlling thepivoting movement of the arms 15 is not shown for the sake of simplicityof representation. Also this actuator can be controlled by the centralcontrol unit 10.

The winding cradle formed by the winding rollers 3 and 9 is labeled as awhole with number 19. At every winding cycle a winding rod is insertedin said cradle 19 to form a reel, with a procedure described later on.

Around the winding roller 3 the web material N is fed, coming from adownstream station and passing around a bow roller 21 to enlargetransversally the web material N. The winding roller 3 can be wholly orpartially covered with a material having a high friction coefficient todraw the web material and impart the rotation movement to the reel beingformed in the winding cradle 19. In a similar manner also the roller 9can be wholly or partially covered with a material with high frictioncoefficient. In some embodiments the roller 9 has annular grooves,inside which the belts 11 are guided. These latter can be in turncovered with, or produced in, a material with high friction coefficient.

Adjacent to the rewinding machine 1, a station 2 is arranged forreceiving the single reels formed by the rewinding machine 1, and fromthis station the reels are then unloaded towards a storage area, afurther processing line or other. As it will be clearly apparent fromthe description below, the reels are unloaded from the cradle formed bythe rollers 3 and 9 on the station 2 through a pivoting movement of thearms 15 and of the belts 11 around the axis 9A of the winding roller 9.

A double guide 23 extends around the first winding roller 3. More inparticular, two guides 23 are provided at the two ends of the windingroller 3, each of which has a curved guiding surface with a profilegradually moving towards the cylindrical surface of the winding roller 3to allow the winding rods to move gradually towards said roller. Thewinding rods, indicated with A1, A2, are fed one after another by awinding rod inserter 25 for introducing the rods in the winding cradle19. The inserter 25 can be designed in a known manner and has engagementmembers for engaging the ends of the winding rods A and is provided witha rotation movement around the axis 3A of the winding roller 3.

The machine described above operates as follows.

FIG. 1 shows an initial winding phase of a first reel B1 around a firstwinding rod A1. In this phase the web material N is fed around an upperportion of the cylindrical surface of the winding roller 3 and windsaround the rod A1 to form a reel B1 in contact with the winding rollers3 and 9. The rotation speed of the rollers 3 and 9 is substantiallyequal and it can achieve very high values, in the order of 1500-2000m/min. It should be understood that these and other speed values in thepresent description are indicated purely by way of non-limiting example.

As the diameter of the reel B1 increases, the reel centre moves awayfrom the pair of winding rollers 3 and 9 and the reel periphery startstouching the upper branch of the belts 11 contributing to impart therotation movement to the reel and thus to increase the diameter thereof.The contact between belts 11 and reel B1 being formed allows a moreregular winding.

FIG. 2 shows the final winding phase of the reel B1. It is in contact ina limited area of the winding roller 3 and in a limited area of thewinding roller 9, as well as along an arc of the upper branch of thebelts 11. Once the desired diameter, i.e. the quantity of wound webmaterial set by the operator, has been achieved, the machine performsthe replacement cycle for replacing the formed reel B1 with a newwinding rod A2. To this end, the speed of the machine is reduced,without however stopping the movement thereof. In some embodiments,starting from the arrangement of FIG. 2, the web material speed isreduced from the steady-state speed (1000-2000 m/min) to a speed ofabout 100 m/min or, more in general, to a reduced replacement speed.

Subsequently (FIG. 3) the arms 15 are lowered rotating in clockwisedirection (in the figure), so as to bring the belts 11 in such aposition to allow the reel B1 to roll towards the unloading station 2.In this phase auxiliary small planes 16 integral with the arms 15 areadvantageously aligned with an inclined unloading plane 31, with whichthe unloading station 2 is provided. The reel B1 rolls on the belts 11,on the small planes 16 and lastly achieves the inclined unloading plane31 to be definitely unloaded in the station 2, taking the positionindicated in FIG. 4. To move the reel B1 away from the cradle 19 apushing member can be used, known and therefore not shown, for exampleof the type described in the prior art documents cited in theintroduction of the present description. In this phase, the web materialN is still intact and extends therefore around a portion of windingroller 9, and around a portion of the winding roller 3, crossing thecradle 19.

In this phase the inserter 25 introduces a new winding rod A2, which isdriven along the guides 23 from the initial position indicated withA2(X) in FIG. 3 to the final position indicated with A2(Y) in thesubsequent FIG. 4. During this movement towards the winding cradle 19the rod A2 is held at the ends of the inserter 25, which graduallyrotates around the axis 3A of the winding roller 3. The shape of theguides 23 is such that at a given point the rod A2 presses against thewinding roller 3 holding the web material N between the winding rod A2and said roller 3. In some embodiments, on the winding rod A2 a windingcore made of cardboard is provided, advantageously provided for instancewith a strip of double-sided adhesive or with other adhesive means that,thanks to the contact with the web material N and to the pressure on theweb material N comprised between the winding rod A2 and the windingroller 3, cause the adhesion of the web material N and the beginning ofthe material winding, with consequent severing, breaking or interruptionof the material in a position comprised between the contact point withthe new winding rod A2 and the touching point with the winding roller 9.

Severing can be performed or facilitated through known manual orautomatic auxiliary means. Advantageously, in some embodiments the rodcan be previously accelerated so as to obtain a peripheral speed nearlyequal to the speed of contact with the roller 3.

In this arrangement, whilst the reel B1 is transferred to the station 2,a second reel of web material B2 begins winding around the winding rodA2. In this phase the winding movement is imparted only by the windingroller 3, as the rod A2 is maintained in contact only with this rollerdue to the engagement with the inserter 25. The winding speed islimited, due to the slowdown of the machine in this replacement phase.

Subsequently (FIG. 4), when the reel B1 has been discharged from thebelts 11 and has taken the final position shown in FIG. 4, the arms 15can be raised again rotating around the axis 9A so as to move to theposition of FIG. 4 and the winding rod A2 can be released in the windingcradle 19 contacting also the second winding roller 9 and the belts 11.In this phase the inserter 25 can release the winding rod A2 and returnin its starting position, where it takes a new rod A3 for the subsequentreplacement cycle.

Winding continues around the winding rod A2 that in this phase touchesboth the winding rollers 3 and 9 and receives therefore the windingmotion by both the winding members 3, 5. These latter can be graduallyaccelerated until the steady-state speed again. The winding cyclecontinues with increase in the diameter of the second reel B2 as shownin FIG. 5.

In the meanwhile the inserter 25 is returned to the initial position toreceive a third winding rod A3, which will replace, with a cycle similarto that described above, the reel B2 when this latter will be completelywound.

During the unloading phase (FIG. 3), thanks to the fact that the rollers3 and 9 are actuated by two independent motors 7 and 8, it is possiblefor the motion of the winding roller 9, and therefore of the belts 11driven around it, to be controlled according to the unloading needs ofthe reel B1, if necessary winding again the end part of the web materialN, independently of the rotation conditions of the roller 3, that willdepend upon the requirements of starting winding around the rod A2.

FIGS. 6 to 14 show a machine according to the invention in a differentembodiment and the corresponding sequence of winding and replacing aformed reel with a new winding rod.

The machine, indicated as a whole with number 101, comprises a firstwinding member comprising a first winding roller 103. The machinefurthermore comprises a second winding member, which in turn comprises asecond winding roller 105, a third winding roller 107 and a fourthwinding roller 109. The set of rollers forming the first winding memberand the second winding member defines a winding cradle. As will be moreapparent below, the second winding member has a variable conformation,i.e. the arrangement of the rollers defining the second winding memberis changed during the winding cycle to allow unloading the formed reeland starting winding the new reel with a substantially continuousoperation of the machine.

Adjacent to the first winding roller 103 a so-called bow roller 111 isarranged to feed the web material N eliminating the wrinkles thereofand/or enlarging the longitudinal cuts with which the web material canbe subdivided into a plurality of strips that are simultaneously woundaround a plurality of winding cores driven on a same winding rod orspindle.

The winding rollers 103, 105, 107 and 109 advantageously havesubstantially parallel axes of rotation. In some embodiments the rollers103 and 105 are provided with fixed axes and they have therefore acentre-to-centre distance that doesn't change during all the cycle ofwinding and replacing a wound reel with a new winding rod. The rollers103 and 105 advantageously define a nip or seat for resting and rotatingthe reel being wound.

The winding rollers 107 and 109 forming, along with the winding roller105, the second winding member, advantageously have movable axes ofrotation to perform a series of operations on the reel during thereplacement steps, i.e. the steps of unloading the finished reel andinserting the new winding rod, as well as during the initial phase ofwinding a new reel, as it will be described in greater detail hereunderwith reference to the sequence of FIGS. 6 to 14.

In this embodiment the second winding member is therefore substantiallyconfigured as a plurality or cluster of winding rollers 105, 107, and109. The arrangement or conformation of this second winding member isvariable, thanks to the fact that the axes of rotation 105A, 107A, and109A of the rollers 105, 107, and 109 respectively move relative oneanother thus changing the relative position and the distance between thevarious rollers of the rewinding machine 101.

The roller 105 and the axis of rotation 105A thereof are preferablyfixed with respect to a bearing structure of the machine, whilst therollers 107 and 109 with the respective axes 107A and 109A of rotationcan move one with respect to the other and both with respect to thewinding roller 105. The translation movement of the axes of rotation107A, 109A of the rollers 107 and 109 can be obtained with an adequatesystem of guides and actuators, not shown in detail in the drawing.

In some embodiments the rollers 103, 105, 107, and 109 can be driveninto rotation by two or more independent motors. Independent motorsmeans motors that can rotate with speeds different from one another,advantageously under the control of a programmable central processingunit. The speed of the rollers changes in particular during the phase ofreplacing a wound reel with a new winding rod. In particular, therollers 103 and 105 can be advantageously actuated by independentmotors, so as to make these rollers rotate with different speeds in atleast some phases of the winding cycle.

Instead of independent motors systems can be used to vary the speed ofrotation of one or the other of two or more rollers actuated by a commonmotor. These rotation speed change systems can comprise gear motors andauxiliary motors for adjusting the speed of rotation of the outlet shaftof the gear motor relative to the inlet speed of the gear motor.

Advantageously, to the first winding roller 103 an inserter 113 isassociated, mounted so that it can rotate according to the double arrowf₁₁₃ in one direction and in the other around the axis of rotation 103Aof the first winding roller 103.

Adjacent to the set of rollers forming the first winding member and thesecond winding member, a station 102 is arranged for receiving the reelsformed in the rewinding machine 101. The receiving station 102 comprisesa rest surface 102A fixed to a frame 104. In some embodiments the frame104 pivots according to the double arrow f₁₀₄ around an axis 104A forexample by means of an actuator, for instance a cylinder-piston actuator106, for the purposes described hereunder with reference to theoperative sequence shown in FIGS. 6 to 14. In other embodiments theframe 104 can be provided with a translation or roto-translationmovement to move the formed reel away from the rewinding machine 101.

In some embodiments, an auxiliary winding roller 115 is arranged betweenthe winding roller 103 and the winding roller 105 of the second windingmember. In some embodiments the auxiliary winding roller 115 has adiameter smaller than that of the first winding roller 103 and of thesecond winding roller 105. In some embodiments the axis 115A of theauxiliary winding roller 115 is fixed. In other embodiments (describedhereunder) the axis of the auxiliary winding roller 115 is movable forinstance in a substantially vertical direction.

In some embodiments, one or more series of nozzles are arranged in thespace between the first winding roller 103 and the second winding roller105 to generate air jets. In FIGS. 6 to 14 two series of nozzles 117 and119 are provided, interposed in the nip between the rollers 103, 115 andbetween the rollers 115 and 105. The air jets generated by the nozzles117, 119 facilitate the start of winding a new reel around a new windingrod, as it will be described in greater detail hereunder.

Advantageously, in some embodiments to the first winding roller 103guides 123 are associated that, analogously to what has been illustratedwith reference to the guides 23 of FIGS. 1 to 5, form a support for theends of a winding rod A, engaged by the inserter 113, to allow a gradualmovement of the rod towards the first winding roller 103.

After having illustrated the main elements of the rewinding machine inthis second embodiment, a first winding method that can be performedwith this machine will now be described, illustrated schematically inthe sequence of FIGS. 6 to 14.

In FIG. 6 a first reel B1 is being wound around a first winding rod A1.The reel B1 is rotating according to the arrow f_(B) (incounterclockwise direction in the figure) around its own axis. The reelB1 is resting in the seat or cradle formed by the first winding roller103 and by the second winding roller 105. The rollers 103 and 105 rotate(in clockwise direction in the figure) with a peripheral speedsubstantially corresponding to the peripheral speed of the reel B1,corresponding to the feed speed of the web material N, according to thearrow f_(N). In this phase of the winding cycle also the third windingroller 107 and the fourth winding roller 109 rotate (in clockwisedirection in the figure) substantially at the same peripheral speed asthe winding rollers 103 and 105. A second winding rod A2 is arranged inthe inserter 113 and is temporarily still.

Once the required web material has been wound around the reel B1, thereplacing phase starts, involving removal of the reel B1, severing ofthe web material N, introduction of the second winding rod A2 and startwinding of a new reel B2 around the second winding rod A2.

To this end, in an advantageous embodiment, in the arrangement of FIG. 6a phase already starts of slowdown of the machine, reducing the feedspeed of the web material N. At the same time the peripheral speed ofthe winding rollers 103, 105, 107, and 109 is reduced. Typically, insome embodiments the steady-state winding speed, i.e. the speed outsidethe replacing phase, can be around 1000-2000 m/min. The machine isslowed down from this winding speed for instance to about 100-200 m/min,preferably 50/150 m/min, for instance about 100 m/min. The speed valuesmust be intended just as non-limiting examples.

FIG. 7 shows the subsequent phase of the replacing cycle. During thisphase the reel B1 is moved towards an unloading area through atranslation movement of the third winding roller 107 and of the fourthwinding roller 109, that move according to the arrows f₁₀₇ and f₁₀₉respectively. In this phase all the winding rollers are still inrotation and the reel B1 continues winding at a low speed. It is incontact with the second winding roller 105, the third winding roller 107and the fourth winding roller 109.

To obtain a more gradual and uniform start of the winding of a new reelB2 around the second winding rod A2, this latter is driven into rotationby a member, not shown, preferably until it achieves a peripheral speedequal to the speed of the winding roller 103 and to the feed speed ofthe web material N during the replacement phase.

In the subsequent phase, shown in FIG. 8, the inserter 113, rotatingaround the axis 103A of the first winding roller 103, brings the secondwinding rod 102 gradually towards the winding cradle, and more inparticular towards the rest and rotation seat defined by the firstwinding roller 103 and by the second winding roller 105. In thisrotation movement around the axis 103A of the first winding roller 103,the rod rests with its ends on the guides 123 that are suitably shapedto move the axis of the second winding rod A2 gradually towards thecylindrical surface of the first winding roller 103. In this phase thefirst reel B1 continues rotating at the replacement speed, maintainedinto rotation by the winding rollers 103, 107, and 109.

According to a preferred embodiment of the invention, at this point astep is performed of forming a loop of web material N to obtain severingof the web material N and to form a tail end that remains wound aroundthe reel B1 and a head end that winds around the second winding rod A2.

FIG. 9 shows the phase of forming the loop and severing the webmaterial. In this embodiment the winding rollers 105, 107, and 109further slow down, whilst the winding roller 103 continues rotating atthe reduced speed to which the machine has been brought during theprevious operating phase. Following this slowdown, the quantity of webmaterial between the second winding rod A2 and the contact point of thereel B1 on the second winding roller 105 increases, with consequentformation of a loop of web material, indicated with A_(N). In someembodiments the nozzles 117 and 119 are actuated by generating air flowspushing the loop of web material AN upwards, causing tensioning andsevering of the web material N in an intermediate position between thesecond winding rod A2 and the rest point of the reel B1 on the windingroller 105. In combination with, or alternatively to, the air flows,severing of the web material can be obtained by providing an adhesivemeans on the winding rod A2, for example a strip of double-sidedadhesive, a glue, a suction system inside the rod or any other meanscausing the adhesion of the web material to the outer surface of thewinding rod A2. When, due to the gradual rotation of the inserter 113around the axis 103A, it is brought in contact with the web material Ndriven around the first winding roller 103, the adhesion occurs of theweb material N on the second rod A2, which, rotating in the windingdirection, causes the start of the winding of the web material N aroundthe second winding rod A2. With or without the aid of the air flowsgenerated by the nozzles 117 and 119, this causes severing of the webmaterial in an adequate position along the loop A_(N) formed in themanner described above.

Preferably, as shown in FIG. 10, the subsequent phase of the replacementcycle entails stopping the rotation of the second winding roller 105, ofthe third winding roller 107 and of the fourth winding roller 109, i.e.of the cluster of winding rollers forming the second winding member. Inthis phase the web material N continues winding around the secondwinding rod A2 which remains engaged by the inserter 113 and pressedagainst the cylindrical surface of the first winding roller 103. Thislatter gradually accelerates so as to bring the winding speed to thesteady-state value (for instance 1000-2000 m/min).

In the illustrated embodiment, in the subsequent phase shown in FIG. 11the inserter 113 continues rotating around the axis 103A of the firstwinding roller 103, bringing the second winding rod A2 with the new reelB2 being formed around it in the space defined between the first windingroller 103 and the second winding roller 105. In this embodiment, due tothis movement and to the increase in its diameter, the second reel B2contacts also with the auxiliary winding roller 115 rotating at aperipheral speed corresponding to the feed speed of the web material Nand to the speed of rotation of the first winding roller 103.

The third winding roller 107 translates upwards and the fourth windingroller 109 translates horizontally pushing the reel B1 towards theunloading area defined by the station 102. An intermediate plane 130arranged between the second winding roller 105 and the surface 102Aallows the first reel B1, pushed by the fourth winding roller 109, toroll until to be completely in the unloading station 102 (FIG. 12). Thismovement frees the area above the rest and rotation seat defined by thefirst winding roller 103 and by the second winding roller 105. In thisway the third winding roller 107 and the fourth winding roller 109 canbe arranged above the second winding roller 105 and the rest androtation seat defined by the first winding roller 103 and by the secondwinding roller 105. The fourth winding roller 109 and preferably alsothe third winding roller 107 return to the steady-state speed ofrotation, with a peripheral speed corresponding to the feed speed of theweb material. The second winding roller 105 is also driven into rotationagain and gradually accelerated until to achieve the peripheral speedcorresponding to the feed speed of the web material.

As shown in FIG. 12, the fourth winding roller 109 moves towards thesecond reel B2 being formed. Therefore in this phase, whilst the firstreel B1 is in the unloading station 102, the second reel B2 windingaround the second winding rod A2 is in contact with three windingrollers and more precisely: the first winding roller 103, and the secondand fourth winding roller 105, 109 of the second winding member.

In the subsequent FIG. 13 the phase is shown wherein also the thirdwinding roller 107, that has been brought again to a peripheral speedequal to the feed speed of the web material N, contacts the second reelB2 winding around the second winding rod A2. In this phase the reel B2is in contact with five winding rollers.

The second winding rod A2 has been released by the inserter 113 that cangradually return in the initial position to receive a new winding rod,as shown in the subsequent FIG. 14. This new winding rod can be the rodA1 that has been removed from the reel B1 that, with a pivoting of theframe 104, is unloaded towards a storage area, a transferring system orother.

In the meanwhile the second reel B2 continues winding and the increasein its diameter is allowed by a gradual displacement of the thirdwinding roller 107 and of the fourth winding roller 109, whilst thecontact with the auxiliary winding roller 115 is lost. Therefore in thisphase the second reel B2 being wound is in contact with the firstwinding member constituted by the first winding roller 103 and with thesecond winding member constituted by the cluster of winding rollers 105,107, and 109. When the reel B2 has achieved the desired diameter, i.e.the required quantity of web material N, the replacement cycle startsagain starting from the arrangement of FIG. 6.

In the sequence of FIGS. 15 to 23 a different method is illustrated toperform the replacement cycle of the finished reel B1 with a new windingrod A2 and start winding a new reel B2 on the new winding rod A2 usingthe same machine illustrated in FIGS. 6 to 14.

FIG. 15 shows the final phase of winding the first reel B1, similarly toFIG. 6. FIG. 16 illustrates the start of the ejection of the formed reelB1. This phase corresponds substantially to the phase of FIG. 7. Bycomparing FIGS. 7 and 16 it is clear that in this operating mode thethird winding roller 107 is moved away from the reel B1 and is not usedto perform the phase of slowdown and ejection of the first reel B1. Inthis embodiment, in order to eject the first reel B1 from the rest androtation seat only the fourth winding roller 109 is used whilst thethird winding roller 107 is raised towards a position from which it willbe then brought again near the second winding roller 103.

In FIG. 17, corresponding to FIG. 8, the start is shown of the contactbetween the second winding rod A2 and the web material N. In FIG. 18 thephase is illustrated of severing the web material to form the head endand the tail end. In FIG. 19 the second reel B2 starts winding aroundthe second winding rod A2, whilst the first reel B1 is in contact withthe second winding roller 103 and with the fourth winding roller 109that can stop rotating.

In FIG. 20 the second reel B2 being formed around the second winding rodA2 (still engaged by the inserter 113) is brought in contact not onlywith the first winding roller 103, but also with the auxiliary windingroller 115. The fourth winding roller 109, moving from left to the right(in the figure) makes the first reel B1 to roll towards the unloadingstation 102. In FIG. 21 the first reel B1 is housed in the unloadingstation 102, the fourth winding roller 109 has been brought in contactwith the second reel B2 and the third winding roller 107 is near thesecond winding roller 105 and has passed above and around the completedreel B1.

In FIG. 22 the second reel B2 is winding in contact with the fivewinding rollers 103, 105, 107, 109 and 115 that are brought again to thesteady-state or winding speed (typically 1000-2000 m/min). The inserter113 has been brought again in the position of receiving a new windingrod, whilst the previously formed reel B1 is moved towards the outlet bypivoting of the structure 104.

In FIG. 23, corresponding to FIG. 14, the second reel B2 being formedaround the second winding rod A2 is in contact with the winding rollers103, 105, 107 and 109, whilst it has lost the contact with the auxiliarywinding roller 115 due to the increase in its diameter.

Once the reel B2 has achieved the desired dimension, the replacementcycle starts again starting from the condition of FIG. 15.

In the sequence of FIGS. 24 to 32, a modified embodiment is shown,wherein the auxiliary winding roller 115 is provided with an upwards anddownwards translation movement according to the double arrow f_(115,) soas to remain in contact with the reel being formed until the finaldiameter is achieved, as shown in FIG. 24. To this end the auxiliarywinding roller 115 is gradually raised from the initial position (FIG.29) until the final position (FIG. 24). Otherwise, the replacement cyclecan be substantially equal to that described with reference to the twosequences of FIGS. 6 to 14 or to that illustrated in FIGS. 15 to 23.

In the sequence shown in FIGS. 24 to 32, the third winding roller 107accompanies the deceleration and the unload of the first reel B1,similarly to what has been described with reference to the sequence ofFIGS. 6 to 14, but it must be understood that in this embodiment againthe replacement cycle can be modified so that the third winding roller107 doesn't participate in the translation and unloading phase of thereel B1, but moves away from the reel B1 before the latter starts theslowdown phase.

In summary, and with reference to the sequence illustrated in FIGS. 6 to14, the cycle shown in the sequence of FIGS. 24 to 32 is as follows.

FIG. 24 shows the completion of winding the reel B1, in contact with thefive winding rollers 103, 105, 107, 109 and 115. The feed speed of theweb material is equal to the steady-state speed (for example 1000-2000m/min) corresponding to the peripheral rotation speed of all the windingrollers. Once the desired quantity of web material around the reel B1has been achieved, the machine is slowed down, bringing the feed speedof the web material as well as the peripheral speeds of the variousrollers to the replacement speed. A second winding rod A2 is arranged inthe inserter 113.

In FIG. 25 the third winding roller 107 and the fourth winding roller109 forming part of the cluster of the rollers defining the secondwinding member start to translate towards the right in the figure,displacing the formed reel B1 towards the unloading section 102, andtherefore moving it away from the first winding roller 103 and removingit from the rest and rotation seat defined by the first winding roller103 and by the second winding roller 105. Preferably in this phase thewinding rod A2 engaged by the inserter 113 starts rotating and isbrought to a peripheral speed approximately equal to the reduced feedspeed of the web material N.

In FIG. 26 the inserter 113, pivoting around the axis 103A of thewinding roller 103, brings the second winding rod A2 in contact with theweb material N that is held between the winding rod A2 and thecylindrical surface of the first winding roller 103.

In FIG. 27 severing of the web material is shown, if necessary with theaid of the air jets generated by the nozzles 117 and 119. The speed ofrotation of the reel B1 is furthermore slowed down by reducing theperipheral speed of the winding rollers 105, 107, and 109 to form theloop A_(N) of web material between the point of contact of the reel B1and the winding roller 105 and the new winding rod A2.

In FIG. 28 the second winding roller 105, the third winding roller 107and the fourth winding roller 109, i.e. the cluster of winding rollersforming the second winding member, stop, whilst the first winding roller103 starts accelerating, until achieving the winding steady-state speed.The second reel B2 continues winding in contact only with the firstwinding roller 103, the second winding rod A2 still remaining engaged bythe inserter 113 that provides to maintain the second reel B2 pressedagainst the first winding roller 103.

In FIG. 29 the third winding roller 107 moves away from the reel B1 andstarts its movement of passing over the reel B1 to achieve the windingposition again. The fourth winding roller 109 pushes the formed reel B1in the unloading station 102, so that the reel B1 loses the contact withthe second winding roller 105. The inserter 113 is furthermore loweredbringing the second reel B2 in contact with the auxiliary winding roller115.

In FIG. 30 the fourth winding roller 109, which has been accelerated tothe winding speed, contats the second reel B2. The reel B2 is thereforein contact with three winding rollers 103, 115 and 109. The inserter 113can be unreleased from the second winding rod A2 and returns in theloading position, as shown in FIG. 31. In this arrangement also thethird winding roller 107, which has returned to the peripheral speedcorresponding to the winding speed, is in contact with the second reelB2. Winding of the reel B2 continues in contact with the five windingrollers 103, 115, 105, 107 and 109, until the final diameter is achieved(FIG. 32 and subsequently FIG. 24) to start a new replacement cycle.

FIGS. 33 to 40 show a further embodiment of the machine according to theinvention. The same numbers indicate parts identical or equivalent tothose in FIGS. 6 to 32.

In this embodiment the rewinding machine comprises a first windingmember comprising a first winding roller 103 and a second winding membercomprising a cluster of three winding rollers 105, 107 and 109,indicated hereunder as second winding roller 105, third winding roller107 and fourth winding roller 109. The winding rod inserter is againlabeled 113. This embodiment lacks the auxiliary winding roller 115 anda single series of compressed air nozzles 117 can be provided, arrangedin the space or nip between the first winding roller 103 and the secondwinding roller 104 below the plane on which the axis of rotation 103A ofthe first winding roller 103 and the axis of rotation 105A of the secondwinding roller 105 are placed.

With reference to the sequence of FIGS. 33 to 40, in a possibleembodiment the machine illustrated herein performs a cycle of replacingthe formed reel B1 with a new winding rod or core A2 as follows.

In FIG. 33 the reel B1 is in the final winding phase. The rewindingmachine starts to slow down from the steady-state speed to thereplacement speed. In FIG. 34 the second winding rod A2 is engaged bythe inserter 113. In FIG. 35 the third winding roller 107 and the fourthwinding roller 109 of the second winding member start to move the reelB1 towards the unloading area in the unloading station 102. The reel B1is still in contact with the three rollers 105, 107, and 109 rotating atreduced speed. The new winding rod A2 is moved towards the rest andwinding seat defined between the first winding roller 103 and the secondwinding roller 105.

In FIG. 36 the loop A_(N) of web material is formed with or without theaid of the air flows generated by the nozzles 117. The winding rollers105, 107 and 109 have furthermore decelerated with respect to the feedspeed of the web material N, to allow the formation of the loop asdescribed above.

In FIG. 37 the completed reel B1 is unloaded in the unloading station102 whilst the third winding roller passes over the reel B1 and thefourth winding roller 109 moves towards the cradle or rest and windingseat formed by the rollers 103 and 105. The second winding rod A2 isbrought towards the nip between the rollers 103 and 105 so as to bringthe second reel B2 in contact with the first winding roller 103 and withthe second winding roller 105.

In FIG. 38 the fourth winding roller is put in contact with the reel B2that is therefore engaged between the rollers 103, 105 and 109. Theinserter 113 can be released and returns in the initial position (FIG.39), whilst the winding rollers started rotating again at thesteady-state speed. The third winding roller 107 is still in raisedposition.

In the subsequent FIG. 39 also the third winding roller 107 is again incontact with and engaged with the second reel B2 that, in this phase, iswound in contact with the four rollers 103, 105, 107 and 109 rotating atthe winding speed.

In FIG. 40 a subsequent phase is shown, wherein the reel B2 is increasedin diameter whilst a new winding rod has been engaged by the inserter113. From this arrangement the completion of the reel B2 is achieved,i.e. the condition of FIG. 33, to start a new cycle of replacing thecompleted reel with a new winding rod.

FIGS. 41 to 48 show a further embodiment of a rewinding machineaccording to the invention. The same numbers indicate parts identical orequivalent to those of the previously illustrated embodiment.

In the example of FIGS. 41 to 48 the members are also shown that areintended to rotate and translate the axes 109A and 107A of the rollers109 and 107. In the illustrated embodiment the winding roller 107 iscarried by a slide 107B able to slide along a guide 107C. The guide 107Cis pivoted around an axis indicated with 107D, substantially parallel tothe axes of the winding rollers. The slide 107B can slide according tothe double arrow f_(107B) along the guide 107C. A similar arrangement isprovided for the support of the winding roller 109. The latter iscarried by a slide 109B, able to slide in a guide 109C, pivoted aroundan axis 109D. The slide 109B can slide according to the double arrowf_(109B) along the guide 109C and this latter can pivot or rotateaccording to the double arrow f_(109C) around the axis 109D. Therotation around the axes 107D and 109D can be controlled by anelectronically controlled electric motor or other adequate actuator. Thetranslation movement of the slides 107B and 109B along the guides 107Cand 109C can be controlled by a screw and nut screw system, with anelectrically controlled electric motor that controls for instance therotation of the nut screw and that can be carried by the guide.

The machine of FIGS. 41 to 48 furthermore comprises, on both the sidesof the machine, a system for the axial engagement of the winding rods.In some embodiments the engagement systems comprise, on each of the twosides of the machine, a pair of jaws 201 carried by a cursor 203 which,by means of a threaded bar 205 controlled by an actuator 207 (forinstance an electric motor), allows movement in vertical directionaccording to the double arrow f₂₀₃ of the cursor 203 carrying the jaws201. As will be explained hereunder with reference to the operatingcycle illustrated in the sequence of FIGS. 42, 43, 44, 47 and 48, thejaws 201 follow the increase of the reel B that is in the winding cradleand are opened and closed to receive, hold and unload the winding rodson which the reels of web material N are formed.

The functioning sequence illustrated in FIGS. 42, 43, 44, 47, and 48 issimilar to the sequence illustrated in FIGS. 34 to 40 and thereforehereunder the sequence will be described in summary, highlighting onlythe differences with respect to the previously illustrated functioningcycle.

In FIG. 42 a reel B1 is nearly completed. The rod A1, on which it hasbeen wound, has been already released from the jaws 201 that have beenopened. The reel B1 is in contact with the first winding member formedby the winding roller 103 and with the second winding member, formed bythe group or cluster of winding rollers 105, 107 and 109 that rotate inthe directions indicated by the arrows in the figure. A second windingrod A2 is ready at the inserter 113.

With the already described movement of the winding rollers 107 and 109,the reel B1 is moved from the cradle formed by the winding rollers 103and 105 to the position of FIG. 47, wherein it is on the surface 102A inthe unloading station 102. The winding rollers 107 and 109 make amovement similar to that described above to move the formed reel B1 inthe unloading station 102 and to return, firstly the roller 109 and thenthe roller 107, in contact with a second reel B2 that in FIG. 48 is inthe initial winding phase, in contact with the four winding rollers 103,105, 107 and 109.

The figures clearly show the way to obtain the rotation and translationmovement of the rollers 107 and 109 according to the trajectoriesnecessary to unload the reel and start winding a subsequent reel, bymeans using the slides and the guides 107B, 107C and 109B, 109C.

Differently than in the embodiment disclosed above, in this case thewinding rod ends projecting from the reel being formed are engaged bythe jaws 201. As already noted, in the phase shown in FIG. 42 the jaws201 are opened to allow the rod A1 to exit when the reel B1 begins to betranslated towards the unloading station 102. In FIG. 43, while the reelB1 is rolling, under the thrust and the control of the rollers 107 and109, towards the unloading station 102, the two pairs of jaws 201 aremade translate downwards near the nip or cradle formed between thewinding rollers 103 and 105, to receive the second rod A2, which isengaged in this phase by the inserter 113 and begins to be angularlyaccelerated until it achieves a peripheral speed approximately equal tothe feed speed of the web material N. In this phase the winding rollerscan be slowed down from the steady-state winding speed to a lower speed.

FIG. 44 shows the phase of approaching movement of the second rod A2inside the nip or cradle formed between the winding rollers 103 and 105.FIGS. 45 and 46 show an enlargement of the process for severing the webmaterial N in this phase, with the formation of a tail end LC, that endsto wind on the reel B1, and of a head end LT, that begins to wind aroundthe new winding rod A2, adequately brought to the necessary speed ofrotation. The head end LT can be anchored to the second winding rod A2by using a strip of double-adhesive or in any other manner, for examplethrough suction, electrostatic charges, by applying a liquid glue orsimple water, if necessary with starch or other slightly or temporarilyadhesive substance, or in any other adequate manner.

A series of compressed air nozzles 117 arranged between the rollers 105and 107 generate air jets that facilitate the formation of the loop ofweb material. The peripheral speed of rotation of the reel B1 is sloweddown so as to loose the web material N and form the loop and facilitatesevering and beginning of winding the new reel.

In FIG. 47 the reel B1 is resting in the unloading station 102, whilstthe new reel B2 (not shown in FIG. 47) is in the phase of initialwinding, in contact with the winding rollers 103, 105 and 109. The jaws201 on both the sides of the machine are closed and engage the ends ofthe winding rod A2. Adequate supports on the rod or on the jaws allowthe rod to rotate with respect to the jaws around the axis of the rod.

The winding roller 107 is passing over the already formed reel B1 tomove towards the new reel B2 being formed. FIG. 48 shows the positionachieved by the winding rollers 103, 105, 107 and 109 in contact withthe new reel B2, whose rod A2 is engaged at both the ends by the jaws201. The inserter 113 has returned to the position in which it receivesa second winding rod indicated with A3, which will be inserted in themachine at the subsequent replacement cycle. The reel B1 begins theunloading movement by means of a pivoting motion around the axis 104Adue to the effect of the actuator 106. The pairs of jaws 201 begin to begradually raised due to the effect of the threaded bar 205 following thediameter increase of the new reel B2.

FIGS. 49 to 52 show an operating sequence illustrating a way forobtaining the angular acceleration of a new winding rod, indicated withA2, which is engaged by the inserter 113 and inserted in the windingcradle. The specific embodiment illustrated in FIGS. 49 to 52corresponds to that shown in the FIGS. 41 to 48. It should be noted thata similar system for angular acceleration of the winding rod can beadopted also in the other embodiments. In the illustrated example theinserter 113 comprises a pair of jaws 113A, 113B suitable to open andclose to receive, engage and release the winding rods. The jaws 113A and113B are connected to actuators 113C and 113D respectively, whichcontrol the opening and closing movement of the jaws and the movement ofthe winding rod towards the guiding surfaces that control the movementthereof towards the winding roller 103. The jaws and the actuators 113C,113D (in the illustrated example two linear actuators in the form ofhydraulic or pneumatic cylinder-pistons, for example) are carried by arotating equipment 113E, rotating in alternate directions around theaxis 103A of the winding roller 103. The rotation movement according tothe double arrow f₁₁₃ is imparted through a toothed wheel 250 engagingwith toothed sector 113F integral with the rotating equipment 113E. M205schematically indicates a motor, imparting the rotation to the toothedwheel 250. The motor M250 is suitably controlled by a programmablecontrol unit, to which the other motors and actuators of the machine areinterfaced.

The described arrangement is on both sides of the machine, which istherefore provided with a double inserter 113, with two pairs of jaws113A, 113B on both the sides to engage the opposite ends of the windingrods A1, A2, A3.

In the illustrated embodiment, on each side of the machine a respectivewheel 260 is arranged, whose axis is indicated with 260A and is parallelbut not coinciding with the rotation axis 103A of the winding roller103. The wheels 260 are outside the winding roller 103, i.e. flankingit.

With each wheel 260, which advantageously has a substantially smoothcircular edge, treated, if necessary, so as to have a high frictioncoefficient, a toothed wheel 262 is integral, coaxial with each wheeland engaging with a toothed wheel 264, whose rotation is controlled by amotor schematically indicated with M264. Through the motor M264, thatcan be single for the two toothed wheels 264 on the two sides of themachine, the two wheel 260 are driven into rotation at a controlledspeed. Alternatively the wheels 260 can be constituted by smooth orV-shaped pulleys with a plurality of grooves, mounted outside the end ofthe rollers and between sides of the roller and jaws 113A and 113Bdriven into rotation by belts drawn by a single axis moved by a singlemotor.

As it is clear from the sequence illustrated in FIGS. 49 to 52, awinding rod A2 previously inserted in the machine on guiding profiles266 (FIG. 49) is engaged by the jaws 113A and 113B on the two sides ofthe machine and is moved, through rotation of the inserter 113 accordingto f₁₁₃, towards the cradle or nip formed between the winding rollers103 and 105. In this movement, as the centre of rotation of the inserter113 doesn't match with the centre of rotation of the wheels 260, thewinding rod A2 is moved gradually from a position distanced from theedge of the wheels 260 to a position of contact with the wheels (FIG.50).

Continuing the rotation of the inserter 113 from the position of FIG. 50towards the position of FIG. 52, by means of the actuator 113C, providedon both the sides of the machine, the ends of the rod A2 are maintainedin contact with the circular edges of the two wheels 260. These formtherefore the surfaces for guiding the rod and moving it towards thewinding roller 103 and towards the cradle between the winding rollers103 and 105. At the same time the rotation f the wheels 260, controlledby the motor M264, drives in rotation the rod A2, which can be thereforebrought to the desired peripheral speed, advantageously equal to orsubstantially equal to the feed speed of the web material N in thereplacement phase.

In this embodiment the wheels 260 form therefore the guiding surfacesfor the rod A1, A2, A3 and at the same time the means for angularacceleration of the rod.

It is also possible to obtain these two functions through separatemembers, for instance the guide through static surfaces and theacceleration through at least one belt or preferably two belts thatengage tangentially respectively with the one or the other of the twoends of the winding rod while the rod is moved from the initial positionto the final position in the insertion cycle.

As it is clearly apparent from FIGS. 49 to 52, the eccentric arrangementof the wheels 260 on one side and of the winding roller 103 on the otherside allows a gradual passage, without particular stresses, of thewinding rod A2 from the contact with the wheels 260 (FIGS. 49 and 50) tothe position of contact with the winding roller 103 (FIGS. 51 and 52).

It is understood that the drawing only shows an example provided by wayof a practical arrangement of the invention, which can vary in forms andarrangements without however departing from the scope of the conceptunderlying the invention. Any reference numbers in the appended claimsare provided for the sole purpose of facilitating reading of the claimsin the light of the description and the drawing, and do not in anymanner limit the scope of protection represented by the claims.

1. A rewinding machine comprising: at least a first winding member and asecond winding member defining a winding cradle; a winding rod inserterfor introducing a winding rod in said winding cradle to wind a reel ofweb material on said winding rod, said winding rod inserter beingarranged and designed so as to introduce said winding rod against thefirst winding member towards said winding cradle, said second windingmember having a variable configuration and being designed and arrangedto allow a reel, formed around a first winding rod, to be unloaded fromsaid winding cradle, through a change in the configuration of saidsecond winding member, said winding rod inserter, said first windingmember and said second winding member being controlled so that saidfirst reel of web material wound around said first winding rod isunloaded from said winding cradle through a change in the configurationof the second winding member, while said winding rod inserter moves asecond winding rod towards the first winding member and said firstwinding member brings said second winding rod into rotation, wherebywinding a second reel is started, said first winding member comprising afirst winding roller and said second winding member comprising aplurality of further winding rollers controlled to be in contact withthe reel of web material, one or more of said further winding rollersbeing movable such that said first reel moves away from said firstwinding member towards an unloading area maintaining said first reel inrotation and continuing to wind said web material on said first reelwhile said first reel is transferred toward said unloading area and saidwinding rod inserter moves said second winding rod towards said firstwinding member.
 2. A rewinding machine as claimed in claim 1, whereinsaid winding rod inserter is controlled to maintain said second windingrod resting on said first winding member for a first phase of winding ofthe web material around said second winding rod, before said secondwinding rod is brought to rest on the second winding member. 3-11.(canceled)
 12. A rewinding machine as claimed in claim 1, wherein saidsecond winding member comprises a second winding roller, a third windingroller and a fourth winding roller.
 13. A rewinding machine as claimedin claim 12, wherein said first winding roller and said second windingroller define a rest and rotation nip for the reel in winding phase. 14.A rewinding machine as claimed in claim 12, wherein an auxiliary windingroller is arranged between said first winding roller of the firstwinding member and said second winding roller of said second windingmember.
 15. A rewinding machine as claimed in claim 12, wherein saidthird winding roller and said fourth winding roller are arranged andcontrolled to move the first reel away from the first winding member andto transfer the first reel towards said unloading area.
 16. A rewindingmachine as claimed in claim 15, wherein said third winding roller andsaid fourth winding roller are arranged and controlled to transfer saidfirst reel maintaining said first reel in contact with the secondwinding roller.
 17. A machine as claimed in claim 12, wherein saidsecond winding roller, said third winding roller and said fourth windingroller are controlled to decelerate and subsequently to stop therotation of said first reel, said winding rod inserter bringing saidsecond winding rod against said first winding roller starting thewinding of a second reel around said second winding rod in contact withsaid first winding roller.
 18. A rewinding machine as claimed in claim1, further comprising guiding surfaces associated with said firstwinding member, against which the winding rod inserter rests saidwinding rods.
 19. A rewinding machine as claimed in claim 18, whereinsaid guiding surfaces are arranged and designed to define a trajectoryfor introducing the winding rods, extending around the first windingmember and moving gradually towards said first winding member from anon-contact position to a contact position of the winding rod with theweb material driven around said first winding member.
 20. A rewindingmachine as claimed in claim 19, wherein said winding rod insertercomprises an engaging system for the winding rods close to ends of saidwinding rods, said engaging system maintaining the winding rods restingagainst said guiding surfaces.
 21. A rewinding machine as claimed inclaim 18, wherein said guiding surfaces are movable to impart an angularacceleration to said winding rods.
 22. A rewinding machine as claimedclaim 1, wherein said winding rod inserter, said first winding memberand said second winding member are arranged and controlled so that whilesaid first reel is unloaded from the winding cradle, the second windingrod is brought to cooperate temporarily with only the first windingmember, through which the winding of the web material around said newwinding rod starts before said new winding rod starts to co-act with thesecond winding member, while said second winding member unloads saidreel.
 23. A rewinding machine as claimed in claim 1, wherein said firstwinding member and said second winding member are controlled so as todecelerate said first reel at the end of winding of the first reel andbefore an introduction of the second winding rod.
 24. A rewindingmachine as claimed in claim 1, wherein said winding rod inserter isassociated with means for angular acceleration of the second winding rodto drive said second winding rod into rotation.
 25. A method forproducing reels of web material around winding rods, the methodcomprising the steps of: winding a first reel of web material around afirst winding rod in a winding cradle comprising a first winding memberand a second winding member; at an end of winding of said first reel ofweb material, unloading said first reel of web material from saidwinding cradle, inserting a second winding rod in said winding cradle,and winding a second reel of web material around said second windingrod, said first reel of web material being unloaded from said windingcradle through a change in an arrangement of the second winding member,while said second winding rod is driven into rotation by moving saidsecond winding rod towards the first winding member; arranging a firstwinding roller and a second winding roller to define a seat forsupporting and rotating one of the first reel and the second reel duringwinding; arranging a third winding roller and a fourth winding rollerwith movable axes; winding said first reel in said support and rotationseat in contact with at least said first winding roller and said secondwinding roller; continuing winding said first reel of web materialbetween said first winding roller, said second winding roller, saidthird winding roller, and said fourth winding roller; moving said firstreel of web material away from said first winding roller and maintainingsaid first reel of web material in rotation by means of at least saidsecond winding roller and said fourth winding roller and reducing therotation speed of the reel from a winding speed to a replacement speed,said replacement speed being less than the winding speed; bringing saidsecond winding rod against said first winding roller and engaging theweb material between said first winding roller and said second windingrod; severing the web material between the second winding rod and thefirst reel; starting winding said second reel around said second windingrod; moving the first reel of web material away from the second windingroller; bringing the second reel in contact with said second windingroller. 26-28. (canceled)
 29. A method as claimed in claim 25, furthercomprising the step of: moving said first reel of web material away fromsaid first winding roller maintaining said first reel of web materialinto rotation by means of said second winding roller, said third windingroller, and said fourth winding roller.
 30. A method as claimed in claim25, wherein, while the first reel is moved away from the first windingroller, the third winding roller is moved away from the first reel andsaid first reel is transferred towards the unloading area through thefourth winding roller.
 31. A method as claimed in claim 25, furthercomprising the steps of: reducing the rotation speed of the first reelby slowing down the second winding roller, the third winding roller andthe fourth winding roller; moving the third winding roller and thefourth winding roller away from the first reel; accelerating said thirdwinding roller and said fourth winding roller to the winding speed andengaging said second winding rod and the second reel being formed therearound with said third winding roller and said fourth winding roller.32. A method as claimed in claim 25, further comprising the steps of:forming a loop of web material between said first reel and said secondwinding rod by slowing down the rotation speed of said first reel; andholding said loop of web material between said second winding rod andsaid first winding member and causing the severing of the web materialbetween said first reel and said second winding rod.
 33. (canceled) 34.A rewinding machine as claimed in claim 2, wherein said second windingmember comprises a second winding roller, a third winding roller and afourth winding roller.
 35. A rewinding machine as claimed in claim 34,wherein said first winding roller and said second winding roller definea rest and rotation nip for one of the first reel and the second reel inwinding phase.
 36. A rewinding machine as claimed in claim 34, whereinan auxiliary winding roller is arranged between said first windingroller of the first winding member and said second winding roller ofsaid second winding member.
 37. A method as claimed in claim 29,wherein, while the first reel is moved away from the first windingroller, the third winding roller is moved away from the first reel andsaid first reel is transferred towards the unloading area through thefourth winding roller.